This invention relates to tubing connectors and, more particularly, to such connectors wherein the terminating fitting is brazed onto the associated tube.
Tubing connectors for threadless pipe, tubing, conduit and the like are known and have been widely used in the art. The tubes are mechanically connected by means of a threaded fitting which fits over an expansion on the tube end and are screwed together to clamp the expansion to the mating part. These known tubing connectors are exemplified by U.S. Pat. Nos. 2,522,194 and 3,494,643. These known tubing connectors have the disadvantage that they are susceptible to leaking because the mechanical connection compression-fitting relies upon merely clamping the expanded or flared tubing ends against the mating parts. Thus, if the screw fittings are loosened by vibration and the like, leaks can develop. Attempts have been made to braze the tubes onto the terminating fastener or fitting. However, these brazed connections suffer from the disadvantage that the brazing operation requires expensive fixturing and high brazing costs. Further, the brazed quality has been found to be inconsistent, particularly as a result of poor alignment between the tube and the fitting. The effect of these brazing problems also manifests itself by a relatively high percentage of voids in the brazed connection.
These and other disadvantages are overcome by the present invention wherein there is provided a unitary assembly of tubing and an end fitting. The assembly, in accordance with the present invention, virtually eliminates the need for fixturing and therefore reduces the brazing costs. Further, the structural configuration provides accurate alignment between the tube and fitting to further facilitate the brazing operation.